Broadcast on pitch, not without intro from Clare Balding (4,2,3)
I believe the answer is:
thin on top
'balding' is the definition.
(I've seen this before)
'broadcast on pitch not without intro from clare' is the wordplay.
I cannot really see how this works, but
'broadcast' could be 'on' (I've seen this in other clues) and 'on' is found in the answer.
an anagram of 'not' is 'nto' which is within the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for thin on top that I've seen before include "not so hairy now" , "showing scalp?" , "developing a shine for the Head?" , "Result of losing hair, balding" , "State of advancing baldness" .)